* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Microsoft YaHei', Arial, sans-serif;
    background-color: #f5f5f5;
    color: #333;
    line-height: 1.6;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
}

h1 {
    text-align: center;
    margin-bottom: 30px;
    color: #2c3e50;
}

h2 {
    margin-bottom: 15px;
    color: #3498db;
    font-size: 1.5rem;
}

.control-section,
.flashcard-container,
.word-list-section {
    background-color: white;
    border-radius: 8px;
    padding: 20px;
    margin-bottom: 20px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.import-area {
    margin-bottom: 20px;
    padding-bottom: 15px;
    border-bottom: 1px dashed #ddd;
}

.settings-area {
    display: flex;
    flex-direction: column;
}

.setting-item {
    margin-bottom: 15px;
    display: flex;
    align-items: center;
}

.setting-item label {
    width: 150px;
    font-weight: bold;
}

.control-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 10px;
}

input[type="number"] {
    width: 80px;
    padding: 8px;
    border: 1px solid #ddd;
    border-radius: 4px;
}

input[type="file"] {
    margin-bottom: 10px;
    padding: 10px 0;
}

button {
    background-color: #3498db;
    color: white;
    border: none;
    padding: 10px 20px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 16;
    transition: background-color 0.3s;
    margin-right: 10px;
}

button:hover {
    background-color: #2980b9;
}

button:disabled {
    background-color: #95a5a6;
    cursor: not-allowed;
}

#fullscreen-btn {
    background-color: #27ae60;
}

#fullscreen-btn:hover {
    background-color: #219955;
}

#fullscreen-btn:disabled {
    background-color: #95a5a6;
}

.flashcard-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    min-height: 300px;
    perspective: 1000px;
}

.flashcard {
    width: 100%;
    max-width: 400px;
    height: 200px;
    background-color: #fff;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.15);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 20px;
    margin-bottom: 20px;
    transition: transform 0.3s, opacity 0.3s;
    position: relative;
    overflow: hidden;
    transform-style: preserve-3d;
    /* 保持3D效果 */
    backface-visibility: hidden;
    /* 隐藏背面 */
}

.flashcard.flash {
    animation: flash 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}

@keyframes flash {
    0% {
        opacity: 1;
        transform: scale(1) rotateY(0deg);
    }

    25% {
        opacity: 0.5;
        transform: scale(0.95) rotateY(90deg);
    }

    50% {
        opacity: 0;
        transform: scale(0.9) rotateY(180deg);
    }

    75% {
        opacity: 0.5;
        transform: scale(0.95) rotateY(270deg);
    }

    100% {
        opacity: 1;
        transform: scale(1) rotateY(360deg);
    }
}

.word {
    font-size: 2rem;
    font-weight: bold;
    margin-bottom: 15px;
    color: #2c3e50;
}

.meaning {
    font-size: 1.2rem;
    color: #7f8c8d;
    text-align: center;
}

.progress-container {
    width: 100%;
    max-width: 400px;
    height: 6px;
    background-color: #ecf0f1;
    border-radius: 3px;
    overflow: hidden;
}

.progress-bar {
    height: 100%;
    background-color: #3498db;
    width: 0;
    transition: width 0.1s linear;
}

.word-list {
    max-height: 300px;
    overflow-y: auto;
    border: 1px solid #ddd;
    border-radius: 4px;
    padding: 10px;
}

.word-item {
    padding: 8px;
    border-bottom: 1px solid #eee;
    display: flex;
    justify-content: space-between;
}

.word-item:last-child {
    border-bottom: none;
}

.word-english {
    font-weight: bold;
    color: #2c3e50;
}

.word-chinese {
    color: #7f8c8d;
}

/* 全屏模式样式 */
.fullscreen-mode {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: #2c3e50;
    background: linear-gradient(135deg, #2c3e50, #1a2530);
    display: none;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    z-index: 1000;
    overflow: hidden;
    perspective: 1500px;
}

.fullscreen-exit-btn {
    position: absolute;
    top: 20px;
    right: 20px;
    background-color: #e74c3c;
    color: white;
    border: none;
    padding: 15px 25px;
    border-radius: 6px;
    cursor: pointer;
    font-size: 18px;
    font-weight: bold;
    transition: all 0.3s;
    z-index: 1001;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.3);
}

.fullscreen-exit-btn:hover {
    background-color: #c0392b;
    transform: scale(1.05);
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.4);
}

.fullscreen-mode.active {
    display: flex;
    animation: fadeIn 0.3s ease-in-out;
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }

    to {
        opacity: 1;
    }
}

.fullscreen-flashcard-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: #f5f5f5;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    z-index: 1000;
    padding: 20px;
    box-sizing: border-box;
}

.fullscreen-flashcard {
    width: 90%;
    max-width: 800px;
    height: 60vh;
    background-color: white;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.15);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 40px;
    margin-bottom: 20px;
}

@keyframes fullscreen-flash {
    0% {
        opacity: 1;
        transform: scale(1) rotateY(0deg);
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    }

    25% {
        opacity: 0.5;
        transform: scale(0.95) rotateY(90deg);
        box-shadow: 0 15px 40px rgba(0, 0, 0, 0.4);
    }

    50% {
        opacity: 0;
        transform: scale(0.9) rotateY(180deg);
        box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
    }

    75% {
        opacity: 0.5;
        transform: scale(0.95) rotateY(270deg);
        box-shadow: 0 15px 40px rgba(0, 0, 0, 0.4);
    }

    100% {
        opacity: 1;
        transform: scale(1) rotateY(360deg);
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    }
}

.fullscreen-word {
    font-size: 5rem;
    font-weight: bold;
    margin-bottom: 30px;
    color: #2c3e50;
    text-align: center;
}

.fullscreen-meaning {
    font-size: 2.5rem;
    color: #7f8c8d;
    text-align: center;
}

.fullscreen-progress-container {
    width: 80%;
    max-width: 800px;
    height: 10px;
    background-color: rgba(255, 255, 255, 0.2);
    border-radius: 5px;
    overflow: hidden;
    margin-bottom: 30px;
}

.fullscreen-progress-bar {
    height: 100%;
    background-color: #3498db;
    width: 0;
    transition: width 0.1s linear;
}

.fullscreen-btns {
    position: absolute;
    bottom: 20px;
    right: 50px;
}

.exit-fullscreen-btn,
.fullscreen-start-btn,
.fullscreen-stop-btn {
    background-color: white;
    color: #2c3e50;
    border: 2px solid white;
    padding: 12px 24px;
    border-radius: 30px;
    cursor: pointer;
    font-size: 18px;
    transition: all 0.3s;
    position: relative;
    display: inline-block;
    margin-right: 10px;
    bottom: auto;
    right: auto;
    z-index: 100000;
}

.fullscreen-countdown {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 5rem;
    color: #3498db;
    font-weight: bold;
}

/* 响应式调整 */
@media (max-width: 768px) {
    .fullscreen-word {
        font-size: 3.5rem;
    }

    .fullscreen-meaning {
        font-size: 1.8rem;
    }
}

@media (max-width: 480px) {
    .fullscreen-word {
        font-size: 2.5rem;
    }

    .fullscreen-meaning {
        font-size: 1.5rem;
    }

    .container {
        padding: 10px;
    }

    .flashcard {
        height: 180px;
    }

    .word {
        font-size: 1.8rem;
    }

    .meaning {
        font-size: 1rem;
    }

    .setting-item {
        flex-direction: column;
        align-items: flex-start;
    }

    .setting-item label {
        margin-bottom: 5px;
    }
}

.countdown {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 3rem;
    color: #3498db;
    font-weight: bold;
}


@keyframes spin {
    0% {
        transform: rotate(0deg);
    }

    100% {
        transform: rotate(360deg);
    }
}

#excel-file {
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 14px;
}

#excel-file:hover {
    border-color: #3498db;
}

#excel-file::-webkit-file-upload-button {
    visibility: hidden;
}

.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.4);
}

.modal-content {
    background-color: #fefefe;
    margin: 10% auto;
    padding: 20px;
    border: 1px solid #888;
    width: 80%;
    max-width: 600px;
    border-radius: 8px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
}

.close-modal {
    color: #aaa;
    float: right;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
}

.close-modal:hover {
    color: black;
}

#modal-word-list {
    max-height: 400px;
    overflow-y: auto;
    margin-top: 20px;
    padding: 10px;
    background: #f8f9fa;
    border-radius: 4px;
}

/* 模式选择样式 */
.mode-selector {
    margin-bottom: 20px;
    display: flex;
    align-items: center;
}

.mode-selector label {
    margin-right: 15px;
    font-weight: bold;
}

.mode-buttons {
    display: flex;
    gap: 10px;
}

.mode-btn {
    padding: 8px 15px;
    background-color: #f1f1f1;
    color: #333;
    border: 1px solid #ddd;
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.3s;
}

.mode-btn.active {
    background-color: #3498db;
    color: white;
    border-color: #3498db;
}

.image-preview {
    width: 100px;
    height: 100px;
    object-fit: cover;
    border-radius: 4px;
    border: 2px solid transparent;
    cursor: pointer;
    transition: all 0.3s;
}

.image-preview.selected {
    border-color: #3498db;
    box-shadow: 0 0 0 2px rgba(52, 152, 219, 0.5);
}

/* 图片显示样式 */
.image,
.fullscreen-image {
    width: 100%;
    height: 100%;
    justify-content: center;
    align-items: center;
}

.image img,
.fullscreen-image img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
    border-radius: 4px;
}

.fullscreen-image img {
    max-height: 80vh;
}

@keyframes fullscreen-flash {
    0% {
        opacity: 1;
        transform: scale(1) rotateY(0deg);
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    }

    25% {
        opacity: 0.5;
        transform: scale(0.95) rotateY(90deg);
        box-shadow: 0 15px 40px rgba(0, 0, 0, 0.4);
    }

    50% {
        opacity: 0;
        transform: scale(0.9) rotateY(180deg);
        box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
    }

    75% {
        opacity: 0.5;
        transform: scale(0.95) rotateY(270deg);
        box-shadow: 0 15px 40px rgba(0, 0, 0, 0.4);
    }

    100% {
        opacity: 1;
        transform: scale(1) rotateY(360deg);
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    }
}

.fullscreen-word {
    font-size: 5rem;
    font-weight: bold;
    margin-bottom: 30px;
    color: #2c3e50;
    text-align: center;
}

.fullscreen-meaning {
    font-size: 2.5rem;
    color: #7f8c8d;
    text-align: center;
}

.fullscreen-progress-container {
    width: 80%;
    max-width: 800px;
    height: 10px;
    background-color: rgba(255, 255, 255, 0.2);
    border-radius: 5px;
    overflow: hidden;
    margin-bottom: 30px;
}

.fullscreen-progress-bar {
    height: 100%;
    background-color: #3498db;
    width: 0;
    transition: width 0.1s linear;
}

.fullscreen-btns {
    position: absolute;
    bottom: 20px;
    right: 50px;
}

.exit-fullscreen-btn,
.fullscreen-start-btn,
.fullscreen-stop-btn {
    background-color: white;
    color: #2c3e50;
    border: 2px solid white;
    padding: 12px 24px;
    border-radius: 30px;
    cursor: pointer;
    font-size: 18px;
    transition: all 0.3s;
    position: relative;
    display: inline-block;
    margin-right: 10px;
    bottom: auto;
    right: auto;
    z-index: 100000;
}

.fullscreen-countdown {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 5rem;
    color: #3498db;
    font-weight: bold;
}

/* 响应式调整 */
@media (max-width: 768px) {
    .fullscreen-word {
        font-size: 3.5rem;
    }

    .fullscreen-meaning {
        font-size: 1.8rem;
    }
}

@media (max-width: 480px) {
    .fullscreen-word {
        font-size: 2.5rem;
    }

    .fullscreen-meaning {
        font-size: 1.5rem;
    }

    .container {
        padding: 10px;
    }

    .flashcard {
        height: 180px;
    }

    .word {
        font-size: 1.8rem;
    }

    .meaning {
        font-size: 1rem;
    }

    .setting-item {
        flex-direction: column;
        align-items: flex-start;
    }

    .setting-item label {
        margin-bottom: 5px;
    }
}

.countdown {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 3rem;
    color: #3498db;
    font-weight: bold;
}


@keyframes spin {
    0% {
        transform: rotate(0deg);
    }

    100% {
        transform: rotate(360deg);
    }
}

#excel-file,
#image-files {
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 14px;
}

#excel-file:hover,
#image-files:hover {
    border-color: #3498db;
}

#excel-file::-webkit-file-upload-button,
#image-files::-webkit-file-upload-button {
    visibility: hidden;
}

.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.4);
}

.modal-content {
    background-color: #fefefe;
    margin: 10% auto;
    padding: 20px;
    border: 1px solid #888;
    width: 80%;
    max-width: 600px;
    border-radius: 8px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
}

.close-modal {
    color: #aaa;
    float: right;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
}

.close-modal:hover {
    color: black;
}

#modal-word-list {
    max-height: 400px;
    overflow-y: auto;
    margin-top: 20px;
    padding: 10px;
    background: #f8f9fa;
    border-radius: 4px;
}

/* 图片列表模态框样式 */
#modal-image-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: 15px;
    max-height: 500px;
    overflow-y: auto;
    margin-top: 20px;
    padding: 15px;
    background: #f8f9fa;
    border-radius: 4px;
}

.image-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 10px;
    border: 1px solid #eee;
    border-radius: 4px;
    transition: all 0.3s;
    cursor: pointer;
}

.image-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    border-color: #3498db;
}

.image-thumbnail {
    width: 100%;
    height: 120px;
    object-fit: cover;
    border-radius: 4px;
    margin-bottom: 8px;
}

.image-name {
    font-size: 12px;
    color: #666;
    text-align: center;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    width: 100%;
}

#show-image-list-btn {
    background-color: #9b59b6;
}

#show-image-list-btn:hover {
    background-color: #8e44ad;
}

#show-image-list-btn:disabled {
    background-color: #95a5a6;
}

.close-modal:hover {
    color: black;
}

#modal-word-list {
    max-height: 400px;
    overflow-y: auto;
    margin-top: 20px;
    padding: 10px;
    background: #f8f9fa;
    border-radius: 4px;
}

/* 模式选择样式 */
.mode-selector {
    margin-bottom: 20px;
    display: flex;
    align-items: center;
}

.mode-selector label {
    margin-right: 15px;
    font-weight: bold;
}

.mode-buttons {
    display: flex;
    gap: 10px;
}

.mode-btn {
    padding: 8px 15px;
    background-color: #f1f1f1;
    color: #333;
    border: 1px solid #ddd;
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.3s;
}

.mode-btn.active {
    background-color: #3498db;
    color: white;
    border-color: #3498db;
}

/* 图片上传和预览样式 */
.image-preview-container {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 15px;
    max-height: 200px;
    overflow-y: auto;
    padding: 10px;
    border: 1px solid #eee;
    border-radius: 4px;
}

.image-preview {
    width: 100px;
    height: 100px;
    object-fit: cover;
    border-radius: 4px;
    border: 2px solid transparent;
    cursor: pointer;
    transition: all 0.3s;
}

.image-preview.selected {
    border-color: #3498db;
    box-shadow: 0 0 0 2px rgba(52, 152, 219, 0.5);
}

/* 图片显示样式 */
.image,
.fullscreen-image {
    width: 100%;
    height: 100%;
    justify-content: center;
    align-items: center;
}

.image img,
.fullscreen-image img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
    border-radius: 4px;
}

.fullscreen-image img {
    max-height: 80vh;
}

@keyframes fullscreen-flash {
    0% {
        opacity: 1;
        transform: scale(1) rotateY(0deg);
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    }

    25% {
        opacity: 0.5;
        transform: scale(0.95) rotateY(90deg);
        box-shadow: 0 15px 40px rgba(0, 0, 0, 0.4);
    }

    50% {
        opacity: 0;
        transform: scale(0.9) rotateY(180deg);
        box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
    }

    75% {
        opacity: 0.5;
        transform: scale(0.95) rotateY(270deg);
        box-shadow: 0 15px 40px rgba(0, 0, 0, 0.4);
    }

    100% {
        opacity: 1;
        transform: scale(1) rotateY(360deg);
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    }
}

.fullscreen-word {
    font-size: 5rem;
    font-weight: bold;
    margin-bottom: 30px;
    color: #2c3e50;
    text-align: center;
}

.fullscreen-meaning {
    font-size: 2.5rem;
    color: #7f8c8d;
    text-align: center;
}

.fullscreen-progress-container {
    width: 80%;
    max-width: 800px;
    height: 10px;
    background-color: rgba(255, 255, 255, 0.2);
    border-radius: 5px;
    overflow: hidden;
    margin-bottom: 30px;
}

.fullscreen-progress-bar {
    height: 100%;
    background-color: #3498db;
    width: 0;
    transition: width 0.1s linear;
}

.fullscreen-btns {
    position: absolute;
    bottom: 20px;
    right: 50px;
}

.exit-fullscreen-btn,
.fullscreen-start-btn,
.fullscreen-stop-btn {
    background-color: white;
    color: #2c3e50;
    border: 2px solid white;
    padding: 12px 24px;
    border-radius: 30px;
    cursor: pointer;
    font-size: 18px;
    transition: all 0.3s;
    position: relative;
    display: inline-block;
    margin-right: 10px;
    bottom: auto;
    right: auto;
    z-index: 100000;
}

.fullscreen-countdown {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 5rem;
    color: #3498db;
    font-weight: bold;
}

/* 响应式调整 */
@media (max-width: 768px) {
    .fullscreen-word {
        font-size: 3.5rem;
    }

    .fullscreen-meaning {
        font-size: 1.8rem;
    }
}

@media (max-width: 480px) {
    .fullscreen-word {
        font-size: 2.5rem;
    }

    .fullscreen-meaning {
        font-size: 1.5rem;
    }

    .container {
        padding: 10px;
    }

    .flashcard {
        height: 180px;
    }

    .word {
        font-size: 1.8rem;
    }

    .meaning {
        font-size: 1rem;
    }

    .setting-item {
        flex-direction: column;
        align-items: flex-start;
    }

    .setting-item label {
        margin-bottom: 5px;
    }
}

.countdown {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 3rem;
    color: #3498db;
    font-weight: bold;
}


@keyframes spin {
    0% {
        transform: rotate(0deg);
    }

    100% {
        transform: rotate(360deg);
    }
}

#excel-file {
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 14px;
}

#excel-file:hover {
    border-color: #3498db;
}

#excel-file::-webkit-file-upload-button {
    visibility: hidden;
}

.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.4);
}

.modal-content {
    background-color: #fefefe;
    margin: 10% auto;
    padding: 20px;
    border: 1px solid #888;
    width: 80%;
    max-width: 600px;
    border-radius: 8px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
}

.close-modal {
    color: #aaa;
    float: right;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
}

.close-modal:hover {
    color: black;
}

#modal-word-list {
    max-height: 400px;
    overflow-y: auto;
    margin-top: 20px;
    padding: 10px;
    background: #f8f9fa;
    border-radius: 4px;
}

/* 模式选择样式 */
.mode-selector {
    margin-bottom: 20px;
    display: flex;
    align-items: center;
}

.mode-selector label {
    margin-right: 15px;
    font-weight: bold;
}

.mode-buttons {
    display: flex;
    gap: 10px;
}

.mode-btn {
    padding: 8px 15px;
    background-color: #f1f1f1;
    color: #333;
    border: 1px solid #ddd;
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.3s;
}

.mode-btn.active {
    background-color: #3498db;
    color: white;
    border-color: #3498db;
}

/* 图片上传和预览样式 */
.image-preview-container {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 15px;
    max-height: 200px;
    overflow-y: auto;
    padding: 10px;
    border: 1px solid #eee;
    border-radius: 4px;
}

.image-preview {
    width: 100px;
    height: 100px;
    object-fit: cover;
    border-radius: 4px;
    border: 2px solid transparent;
    cursor: pointer;
    transition: all 0.3s;
}

.image-preview.selected {
    border-color: #3498db;
    box-shadow: 0 0 0 2px rgba(52, 152, 219, 0.5);
}

/* 图片显示样式 */
.image,
.fullscreen-image {
    width: 100%;
    height: 100%;
    justify-content: center;
    align-items: center;
}

.image img,
.fullscreen-image img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
    border-radius: 4px;
}

.fullscreen-image img {
    max-height: 80vh;
}

@keyframes fullscreen-flash {
    0% {
        opacity: 1;
        transform: scale(1) rotateY(0deg);
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    }

    25% {
        opacity: 0.5;
        transform: scale(0.95) rotateY(90deg);
        box-shadow: 0 15px 40px rgba(0, 0, 0, 0.4);
    }

    50% {
        opacity: 0;
        transform: scale(0.9) rotateY(180deg);
        box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
    }

    75% {
        opacity: 0.5;
        transform: scale(0.95) rotateY(270deg);
        box-shadow: 0 15px 40px rgba(0, 0, 0, 0.4);
    }

    100% {
        opacity: 1;
        transform: scale(1) rotateY(360deg);
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    }
}

.fullscreen-word {
    font-size: 5rem;
    font-weight: bold;
    margin-bottom: 30px;
    color: #2c3e50;
    text-align: center;
}

.fullscreen-meaning {
    font-size: 2.5rem;
    color: #7f8c8d;
    text-align: center;
}

.fullscreen-progress-container {
    width: 80%;
    max-width: 800px;
    height: 10px;
    background-color: rgba(255, 255, 255, 0.2);
    border-radius: 5px;
    overflow: hidden;
    margin-bottom: 30px;
}

.fullscreen-progress-bar {
    height: 100%;
    background-color: #3498db;
    width: 0;
    transition: width 0.1s linear;
}

.fullscreen-btns {
    position: absolute;
    bottom: 20px;
    right: 50px;
}

.exit-fullscreen-btn,
.fullscreen-start-btn,
.fullscreen-stop-btn {
    background-color: white;
    color: #2c3e50;
    border: 2px solid white;
    padding: 12px 24px;
    border-radius: 30px;
    cursor: pointer;
    font-size: 18px;
    transition: all 0.3s;
    position: relative;
    display: inline-block;
    margin-right: 10px;
    bottom: auto;
    right: auto;
    z-index: 100000;
}

.fullscreen-countdown {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 5rem;
    color: #3498db;
    font-weight: bold;
}

/* 响应式调整 */
@media (max-width: 768px) {
    .fullscreen-word {
        font-size: 3.5rem;
    }

    .fullscreen-meaning {
        font-size: 1.8rem;
    }
}

@media (max-width: 480px) {
    .fullscreen-word {
        font-size: 2.5rem;
    }

    .fullscreen-meaning {
        font-size: 1.5rem;
    }

    .container {
        padding: 10px;
    }

    .flashcard {
        height: 180px;
    }

    .word {
        font-size: 1.8rem;
    }

    .meaning {
        font-size: 1rem;
    }

    .setting-item {
        flex-direction: column;
        align-items: flex-start;
    }

    .setting-item label {
        margin-bottom: 5px;
    }
}

.countdown {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 3rem;
    color: #3498db;
    font-weight: bold;
}


@keyframes spin {
    0% {
        transform: rotate(0deg);
    }

    100% {
        transform: rotate(360deg);
    }
}

#excel-file {
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 14px;
}

#excel-file:hover {
    border-color: #3498db;
}

#excel-file::-webkit-file-upload-button {
    visibility: hidden;
}

.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.4);
}

.modal-content {
    background-color: #fefefe;
    margin: 10% auto;
    padding: 20px;
    border: 1px solid #888;
    width: 80%;
    max-width: 600px;
    border-radius: 8px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
}

.close-modal {
    color: #aaa;
    float: right;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
}

.close-modal:hover {
    color: black;
}

#modal-word-list {
    max-height: 400px;
    overflow-y: auto;
    margin-top: 20px;
    padding: 10px;
    background: #f8f9fa;
    border-radius: 4px;
}

/* 模式选择样式 */
.mode-selector {
    margin-bottom: 20px;
    display: flex;
    align-items: center;
}

.mode-selector label {
    margin-right: 15px;
    font-weight: bold;
}

.mode-buttons {
    display: flex;
    gap: 10px;
}

.mode-btn {
    padding: 8px 15px;
    background-color: #f1f1f1;
    color: #333;
    border: 1px solid #ddd;
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.3s;
}

.mode-btn.active {
    background-color: #3498db;
    color: white;
    border-color: #3498db;
}

/* 图片上传和预览样式 */
.image-preview-container {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 15px;
    max-height: 200px;
    overflow-y: auto;
    padding: 10px;
    border: 1px solid #eee;
    border-radius: 4px;
}

.image-preview {
    width: 100px;
    height: 100px;
    object-fit: cover;
    border-radius: 4px;
    border: 2px solid transparent;
    cursor: pointer;
    transition: all 0.3s;
}

.image-preview.selected {
    border-color: #3498db;
    box-shadow: 0 0 0 2px rgba(52, 152, 219, 0.5);
}

/* 图片显示样式 */
.image,
.fullscreen-image {
    width: 100%;
    height: 100%;
    justify-content: center;
    align-items: center;
}

.image img,
.fullscreen-image img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
    border-radius: 4px;
}

.fullscreen-image img {
    max-height: 80vh;
}

@keyframes fullscreen-flash {
    0% {
        opacity: 1;
        transform: scale(1) rotateY(0deg);
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    }

    25% {
        opacity: 0.5;
        transform: scale(0.95) rotateY(90deg);
        box-shadow: 0 15px 40px rgba(0, 0, 0, 0.4);
    }

    50% {
        opacity: 0;
        transform: scale(0.9) rotateY(180deg);
        box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
    }

    75% {
        opacity: 0.5;
        transform: scale(0.95) rotateY(270deg);
        box-shadow: 0 15px 40px rgba(0, 0, 0, 0.4);
    }

    100% {
        opacity: 1;
        transform: scale(1) rotateY(360deg);
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    }
}

.fullscreen-word {
    font-size: 5rem;
    font-weight: bold;
    margin-bottom: 30px;
    color: #2c3e50;
    text-align: center;
}

.fullscreen-meaning {
    font-size: 2.5rem;
    color: #7f8c8d;
    text-align: center;
}

.fullscreen-progress-container {
    width: 80%;
    max-width: 800px;
    height: 10px;
    background-color: rgba(255, 255, 255, 0.2);
    border-radius: 5px;
    overflow: hidden;
    margin-bottom: 30px;
}

.fullscreen-progress-bar {
    height: 100%;
    background-color: #3498db;
    width: 0;
    transition: width 0.1s linear;
}

.fullscreen-btns {
    position: absolute;
    bottom: 20px;
    right: 50px;
}

.exit-fullscreen-btn,
.fullscreen-start-btn,
.fullscreen-stop-btn {
    background-color: white;
    color: #2c3e50;
    border: 2px solid white;
    padding: 12px 24px;
    border-radius: 30px;
    cursor: pointer;
    font-size: 18px;
    transition: all 0.3s;
    position: relative;
    display: inline-block;
    margin-right: 10px;
    bottom: auto;
    right: auto;
    z-index: 100000;
}

.fullscreen-countdown {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 5rem;
    color: #3498db;
    font-weight: bold;
}

/* 响应式调整 */
@media (max-width: 768px) {
    .fullscreen-word {
        font-size: 3.5rem;
    }

    .fullscreen-meaning {
        font-size: 1.8rem;
    }
}

@media (max-width: 480px) {
    .fullscreen-word {
        font-size: 2.5rem;
    }

    .fullscreen-meaning {
        font-size: 1.5rem;
    }

    .container {
        padding: 10px;
    }

    .flashcard {
        height: 180px;
    }

    .word {
        font-size: 1.8rem;
    }

    .meaning {
        font-size: 1rem;
    }

    .setting-item {
        flex-direction: column;
        align-items: flex-start;
    }

    .setting-item label {
        margin-bottom: 5px;
    }
}

.countdown {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 3rem;
    color: #3498db;
    font-weight: bold;
}


@keyframes spin {
    0% {
        transform: rotate(0deg);
    }

    100% {
        transform: rotate(360deg);
    }
}

#excel-file {
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 14px;
}

#excel-file:hover {
    border-color: #3498db;
}

#excel-file::-webkit-file-upload-button {
    visibility: hidden;
}

.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.4);
}

.modal-content {
    background-color: #fefefe;
    margin: 10% auto;
    padding: 20px;
    border: 1px solid #888;
    width: 80%;
    max-width: 600px;
    border-radius: 8px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
}

.close-modal {
    color: #aaa;
    float: right;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
}

.close-modal:hover {
    color: black;
}

#modal-word-list {
    max-height: 400px;
    overflow-y: auto;
    margin-top: 20px;
    padding: 10px;
    background: #f8f9fa;
    border-radius: 4px;
}

/* 模式选择样式 */
.mode-selector {
    margin-bottom: 20px;
    display: flex;
    align-items: center;
}

.mode-selector label {
    margin-right: 15px;
    font-weight: bold;
}

.mode-buttons {
    display: flex;
    gap: 10px;
}

.mode-btn {
    padding: 8px 15px;
    background-color: #f1f1f1;
    color: #333;
    border: 1px solid #ddd;
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.3s;
}

.mode-btn.active {
    background-color: #3498db;
    color: white;
    border-color: #3498db;
}

/* 图片上传和预览样式 */
.image-preview-container {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 15px;
    max-height: 200px;
    overflow-y: auto;
    padding: 10px;
    border: 1px solid #eee;
    border-radius: 4px;
}

.image-preview {
    width: 100px;
    height: 100px;
    object-fit: cover;
    border-radius: 4px;
    border: 2px solid transparent;
    cursor: pointer;
    transition: all 0.3s;
}

.image-preview.selected {
    border-color: #3498db;
    box-shadow: 0 0 0 2px rgba(52, 152, 219, 0.5);
}

/* 图片显示样式 */
.image,
.fullscreen-image {
    width: 100%;
    height: 100%;
    justify-content: center;
    align-items: center;
}

.image img,
.fullscreen-image img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
    border-radius: 4px;
}

.fullscreen-image img {
    max-height: 80vh;
}

@keyframes fullscreen-flash {
    0% {
        opacity: 1;
        transform: scale(1) rotateY(0deg);
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    }

    25% {
        opacity: 0.5;
        transform: scale(0.95) rotateY(90deg);
        box-shadow: 0 15px 40px rgba(0, 0, 0, 0.4);
    }

    50% {
        opacity: 0;
        transform: scale(0.9) rotateY(180deg);
        box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
    }

    75% {
        opacity: 0.5;
        transform: scale(0.95) rotateY(270deg);
        box-shadow: 0 15px 40px rgba(0, 0, 0, 0.4);
    }

    100% {
        opacity: 1;
        transform: scale(1) rotateY(360deg);
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    }
}

.fullscreen-word {
    font-size: 5rem;
    font-weight: bold;
    margin-bottom: 30px;
    color: #2c3e50;
    text-align: center;
}

.fullscreen-meaning {
    font-size: 2.5rem;
    color: #7f8c8d;
    text-align: center;
}

.fullscreen-progress-container {
    width: 80%;
    max-width: 800px;
    height: 10px;
    background-color: rgba(255, 255, 255, 0.2);
    border-radius: 5px;
    overflow: hidden;
    margin-bottom: 30px;
}

.fullscreen-progress-bar {
    height: 100%;
    background-color: #3498db;
    width: 0;
    transition: width 0.1s linear;
}

.fullscreen-btns {
    position: absolute;
    bottom: 20px;
    right: 50px;
}

.exit-fullscreen-btn,
.fullscreen-start-btn,
.fullscreen-stop-btn {
    background-color: white;
    color: #2c3e50;
    border: 2px solid white;
    padding: 12px 24px;
    border-radius: 30px;
    cursor: pointer;
    font-size: 18px;
    transition: all 0.3s;
    position: relative;
    display: inline-block;
    margin-right: 10px;
    bottom: auto;
    right: auto;
    z-index: 100000;
}

.fullscreen-countdown {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 5rem;
    color: #3498db;
    font-weight: bold;
}

/* 响应式调整 */
@media (max-width: 768px) {
    .fullscreen-word {
        font-size: 3.5rem;
    }

    .fullscreen-meaning {
        font-size: 1.8rem;
    }
}

@media (max-width: 480px) {
    .fullscreen-word {
        font-size: 2.5rem;
    }

    .fullscreen-meaning {
        font-size: 1.5rem;
    }

    .container {
        padding: 10px;
    }

    .flashcard {
        height: 180px;
    }

    .word {
        font-size: 1.8rem;
    }

    .meaning {
        font-size: 1rem;
    }

    .setting-item {
        flex-direction: column;
        align-items: flex-start;
    }

    .setting-item label {
        margin-bottom: 5px;
    }
}

.countdown {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 3rem;
    color: #3498db;
    font-weight: bold;
}


@keyframes spin {
    0% {
        transform: rotate(0deg);
    }

    100% {
        transform: rotate(360deg);
    }
}

#excel-file {
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 14px;
}

#excel-file:hover {
    border-color: #3498db;
}

#excel-file::-webkit-file-upload-button {
    visibility: hidden;
}

.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.4);
}

.modal-content {
    background-color: #fefefe;
    margin: 10% auto;
    padding: 20px;
    border: 1px solid #888;
    width: 80%;
    max-width: 600px;
    border-radius: 8px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
}

.close-modal {
    color: #aaa;
    float: right;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
}

.close-modal:hover {
    color: black;
}

#modal-word-list {
    max-height: 400px;
    overflow-y: auto;
    margin-top: 20px;
    padding: 10px;
    background: #f8f9fa;
    border-radius: 4px;
}

/* 模式选择样式 */
.mode-selector {
    margin-bottom: 20px;
    display: flex;
    align-items: center;
}

.mode-selector label {
    margin-right: 15px;
    font-weight: bold;
}

.mode-buttons {
    display: flex;
    gap: 10px;
}

.mode-btn {
    padding: 8px 15px;
    background-color: #f1f1f1;
    color: #333;
    border: 1px solid #ddd;
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.3s;
}

.mode-btn.active {
    background-color: #3498db;
    color: white;
    border-color: #3498db;
}

/* 图片上传和预览样式 */
.image-preview-container {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 15px;
    max-height: 200px;
    overflow-y: auto;
    padding: 10px;
    border: 1px solid #eee;
    border-radius: 4px;
}

.image-preview {
    width: 100px;
    height: 100px;
    object-fit: cover;
    border-radius: 4px;
    border: 2px solid transparent;
    cursor: pointer;
    transition: all 0.3s;
}

.image-preview.selected {
    border-color: #3498db;
    box-shadow: 0 0 0 2px rgba(52, 152, 219, 0.5);
}

/* 图片显示样式 */
.image,
.fullscreen-image {
    width: 100%;
    height: 100%;
    justify-content: center;
    align-items: center;
}

.image img,
.fullscreen-image img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
    border-radius: 4px;
}

.fullscreen-image img {
    max-height: 80vh;
}

@keyframes fullscreen-flash {
    0% {
        opacity: 1;
        transform: scale(1) rotateY(0deg);
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    }

    25% {
        opacity: 0.5;
        transform: scale(0.95) rotateY(90deg);
        box-shadow: 0 15px 40px rgba(0, 0, 0, 0.4);
    }

    50% {
        opacity: 0;
        transform: scale(0.9) rotateY(180deg);
        box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
    }

    75% {
        opacity: 0.5;
        transform: scale(0.95) rotateY(270deg);
        box-shadow: 0 15px 40px rgba(0, 0, 0, 0.4);
    }

    100% {
        opacity: 1;
        transform: scale(1) rotateY(360deg);
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    }
}

.fullscreen-word {
    font-size: 5rem;
    font-weight: bold;
    margin-bottom: 30px;
    color: #2c3e50;
    text-align: center;
}

.fullscreen-meaning {
    font-size: 2.5rem;
    color: #7f8c8d;
    text-align: center;
}

.fullscreen-progress-container {
    width: 80%;
    max-width: 800px;
    height: 10px;
    background-color: rgba(255, 255, 255, 0.2);
    border-radius: 5px;
    overflow: hidden;
    margin-bottom: 30px;
}

.fullscreen-progress-bar {
    height: 100%;
    background-color: #3498db;
    width: 0;
    transition: width 0.1s linear;
}

.fullscreen-btns {
    position: absolute;
    bottom: 20px;
    right: 50px;
}

.exit-fullscreen-btn,
.fullscreen-start-btn,
.fullscreen-stop-btn {
    background-color: white;
    color: #2c3e50;
    border: 2px solid white;
    padding: 12px 24px;
    border-radius: 30px;
    cursor: pointer;
    font-size: 18px;
    transition: all 0.3s;
    position: relative;
    display: inline-block;
    margin-right: 10px;
    bottom: auto;
    right: auto;
    z-index: 100000;
}

.fullscreen-countdown {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 5rem;
    color: #3498db;
    font-weight: bold;
}

/* 响应式调整 */
@media (max-width: 768px) {
    .fullscreen-word {
        font-size: 3.5rem;
    }

    .fullscreen-meaning {
        font-size: 1.8rem;
    }
}

@media (max-width: 480px) {
    .fullscreen-word {
        font-size: 2.5rem;
    }

    .fullscreen-meaning {
        font-size: 1.5rem;
    }

    .container {
        padding: 10px;
    }

    .flashcard {
        height: 180px;
    }

    .word {
        font-size: 1.8rem;
    }

    .meaning {
        font-size: 1rem;
    }

    .setting-item {
        flex-direction: column;
        align-items: flex-start;
    }

    .setting-item label {
        margin-bottom: 5px;
    }
}

.countdown {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 3rem;
    color: #3498db;
    font-weight: bold;
}


@keyframes spin {
    0% {
        transform: rotate(0deg);
    }

    100% {
        transform: rotate(360deg);
    }
}

#excel-file {
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 14px;
}

#excel-file:hover {
    border-color: #3498db;
}

#excel-file::-webkit-file-upload-button {
    visibility: hidden;
}

.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.4);
}

.modal-content {
    background-color: #fefefe;
    margin: 10% auto;
    padding: 20px;
    border: 1px solid #888;
    width: 80%;
    max-width: 600px;
    border-radius: 8px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
}

.close-modal {
    color: #aaa;
    float: right;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
}

.close-modal:hover {
    color: black;
}

#modal-word-list {
    max-height: 400px;
    overflow-y: auto;
    margin-top: 20px;
    padding: 10px;
    background: #f8f9fa;
    border-radius: 4px;
}

/* 模式选择样式 */
.mode-selector {
    margin-bottom: 20px;
    display: flex;
    align-items: center;
}

.mode-selector label {
    margin-right: 15px;
    font-weight: bold;
}

.mode-buttons {
    display: flex;
    gap: 10px;
}

.mode-btn {
    padding: 8px 15px;
    background-color: #f1f1f1;
    color: #333;
    border: 1px solid #ddd;
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.3s;
}

.mode-btn.active {
    background-color: #3498db;
    color: white;
    border-color: #3498db;
}

/* 图片上传和预览样式 */
.image-preview-container {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 15px;
    max-height: 200px;
    overflow-y: auto;
    padding: 10px;
    border: 1px solid #eee;
    border-radius: 4px;
}

.image-preview {
    width: 100px;
    height: 100px;
    object-fit: cover;
    border-radius: 4px;
    border: 2px solid transparent;
    cursor: pointer;
    transition: all 0.3s;
}

.image-preview.selected {
    border-color: #3498db;
    box-shadow: 0 0 0 2px rgba(52, 152, 219, 0.5);
}

/* 图片显示样式 */
.image,
.fullscreen-image {
    width: 100%;
    height: 100%;
    justify-content: center;
    align-items: center;
}

.image img,
.fullscreen-image img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
    border-radius: 4px;
}

.fullscreen-image img {
    max-height: 80vh;
}

@keyframes fullscreen-flash {
    0% {
        opacity: 1;
        transform: scale(1) rotateY(0deg);
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    }

    25% {
        opacity: 0.5;
        transform: scale(0.95) rotateY(90deg);
        box-shadow: 0 15px 40px rgba(0, 0, 0, 0.4);
    }

    50% {
        opacity: 0;
        transform: scale(0.9) rotateY(180deg);
        box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
    }

    75% {
        opacity: 0.5;
        transform: scale(0.95) rotateY(270deg);
        box-shadow: 0 15px 40px rgba(0, 0, 0, 0.4);
    }

    100% {
        opacity: 1;
        transform: scale(1) rotateY(360deg);
        box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    }
}

.fullscreen-word {
    font-size: 5rem;
    font-weight: bold;
    margin-bottom: 30px;
    color: #2c3e50;
    text-align: center;
}

.fullscreen-meaning {
    font-size: 2.5rem;
    color: #7f8c8d;
    text-align: center;
}

.fullscreen-progress-container {
    width: 80%;
    max-width: 800px;
    height: 10px;
    background-color: rgba(255, 255, 255, 0.2);
    border-radius: 5px;
    overflow: hidden;
    margin-bottom: 30px;
}

.fullscreen-progress-bar {
    height: 100%;
    background-color: #3498db;
    width: 0;
    transition: width 0.1s linear;
}

.fullscreen-btns {
    position: absolute;
    bottom: 20px;
    right: 50px;
}

.exit-fullscreen-btn,
.fullscreen-start-btn,
.fullscreen-stop-btn {
    background-color: white;
    color: #2c3e50;
    border: 2px solid white;
    padding: 12px 24px;
    border-radius: 30px;
    cursor: pointer;
    font-size: 18px;
}